The present embodiments relate to the generation of power from temperature differentials.
Exhaust gases from for example a cryogenic freezing system or process typically are discharged outside of the facility directly to the atmosphere. Such exhaust gases are generally very cold, i.e. minus 40° F. to minus 100° F., and in certain applications much colder. Such exhaust gases also have the capacity for significant additional refrigeration loads. It is estimated that from between 15% to 20% of total refrigeration capacity from a cryogenic fluid is lost when the gas is discharged from the freezing process.
It is known that voltage produced is proportional to a temperature difference between two junctions. That is, the proportionality constant alpha (α) is known as the Seebeck coefficient (represented in the equation below), and is often referred to as thermoelectric power or thermopower. A voltage difference produced across terminals of an open circuit made from a pair of dissimilar metals whose two junctions are at different temperatures, is directly proportional to the difference between the hot and cold junction temperatures. Seebeck voltage does not depend on the distribution of temperature along metals between junctions of same, such as is required in a thermocouple.V=α(Th−Tc)
The voltage difference, V, produced across the terminals of an open circuit made from a pair of dissimilar metals, A and B, whose two junctions are held at different temperatures, is directly proportional to the difference between the hot and cold junction temperatures, Th−Tc.